Automatic telephone-exchange system.



F. R. lVIGBERTY.

AUTOMATIC TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED JUET'ES. 2913.

Patent-ed J an. 12, 1915.

VV/fness es.

UNITED STATES OFFICE.

FRANK B. mcBEn'rY, or aiv'rwienr, "BELGIUM, ASSIGNOR T0 wns'rsnn ELECTRIC comramr, or NEW YORK, N. 12, a conceals-Tron or rtnmors.

AUTOMATIC TE'LI'IPHONE-EXCHANGE SYSTEM:

Specification f Letters Patent.

Yatented Jan. 12, 1915.

Application filed June 3, 1913. Serial No. 771,459.

To all whom it may concern 7 Be it known that I, FRANK R. Mcllnnrr, a citizen of the United States, residing at Antwerp, in the province of Antwerp and Kingdom of Belgium, have invented a cer' tain new and useful Improvement in Automatic Telephone -lxchange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to an improvement in automatic and semi-automatic telephone systems and refers more particularly to an improved arrangement of circuits by virtue oi which the speed at which a given connection may be made is increased and the general operation of the connecting apparatus improved.

The invention is particularly applicable to automatic or semiautomatic systems in which a selector switch is governed in its movement by a sending device which in turn is governed in its movement by electrical impulses caused by the movement of the selector switch, the arrangement being such that the sending device is displaced from normal position to a predetermined position, depending upon the terminal it is desired to select, and is stepped back to normal by impulses produced y an interrupter associatedi with the selector switch. Such systems of control are well known in the art and are designated as systems employing the revertive impulse control.

It has been found that in systems of revert-ire impulse control the speed at which a connection may be made depends upon the speed at which the controlling magnets at the sending device and selector switch may be made to respond. It has also been found that such magnets will respond with greater rapidity to impulses formed by breaking of a circuit than to impulses formed by diverting or shunting a part of the current. Therefore, in order to obtain the maximum speed in the invention hereinafter disclosed, he controlling magnets of the sending device and selector are connected in series in a circuit -which is opened and closed by an interrupter associated with the selector switch In order that the selector switch may be more positively controlled and its operation rendered more certain, provision is made for electrically controlling said selector during the time that the main controlling circuit referred to above is interrupted.

The invention is shown in the accompanying revving whichfis a diagrammatic represntation of the system.

The sender maybe at any well known type in which a stepping magnet is used to step a dial or arm to a predetermined point, an in which means are provided to operate a stop relay or the equivalent upon the arrival of the sender arm at such point. The sending device is not illustrated on ,the drawing as its construction and operation are well known. The ordinary steppi'n ma net of a sender, however, is shown at 6% an the stop relay at 68. Obviously, the

sending device may be located either at the subscrihers substation or at the centraloffiee, the operation being the same.

The selector or connector switch, which is employed in the specific embodiment of the invention shown on the dr wing, is substantially the same as that disclosed in the applicants British Patent 1911 to which reference. may more complete description. parts of such a selector switch are shown diagrammatically'on the drawings in which 75 represents a constantly rotating -Shaft, 6 and 7- magnetic disks secured thereto and rotatin therewith. 'Coiiperatin with the disks" 6 an 7, and at right-1mg es thereto, are the dis s 59 and 8. The disks 7 and 59 are flexibly mounted so that they may be drawn into engagement with the disks 6 and 8' when the solenoids 14.- and 58 are onergized. The disk 59 is attached to the spindle 9, which carries a series of movable brushes 10. These brushes are adapted to be moved over a series of stationary contacts 11, which contacts are arranged in rows in a semi-cylindrical contact bank. The brushes 10 are normally held out of conbe Had for a,

tact with the stationary contacts 11, mid are arranged so that a selected set may be" tripped by projections carried by the' spindle 73 in order that the selected set may make contact with the stationary contacts during their movement thereover. The spindle 73 is carried by the disk 8, which also carries the toothed wheel79. The toothed wheel 79 in its rotation acts to vibrate the arm 71 held in contact therewith, by means of spring pressure. The vibration of the arm 71 acts to operate the springs 69 and 70 and to bring the arm 7] in contact with the spring 69. The toothed wheel 79 is provided 10 No. 16,867 of The essential indicated at 57.

at its normal position with a depression of greater depth than at any other portion so that when in normal position the arm 71 may contact with the spring 72 for a urpose to be hereafter described. Carrie by the spindle 9 on the brush frame is an arm 76 which is pivotally mounted, and is adapted to be vibrated by teeth on the stationary segment 12 over which a roller 83 carried by said arm is adapted to ride. The vibration of the arm 76 first makes contact between the arm and the spring 78, and then breaks the contact between springs 77 and 78. A solenoid 58 surrounds the spindle 73, and a solenoid 14 surrounds the shaft 75. Both of these solenoids are provided with two windings and the arrangement is such that when either of the windings of the sole noid 14 is energized, the disks 59 and 6 will be brought into engagement, and when either of the windings of the solenoid 58 is energized, the disks 7 and 8 are brought into engagement. For a more detailed description of the selector switch, reference may be had to applicants British patent referred to above.

In addition to the selector and sending devices above described, a circuit changing device which is known as a sequence switch is used. A switch of this character is shown, for instance, in applicants Patent No. 1,009,080 granted November 21, 1911. Such a sequence switch is shown dia animatically on the drawing. The switc springs, however, are not shown in their actual ar rangement, but are so located as to give a clear arrangement of the circuits. The po; sition in wi lch any of the various contacts 50, 51, 52, etc., are closed, is indicated by numbers placed adjacent to such contacts, each contact being open in all positions except those indicated by such reference numorals, for example, the contact 54 is closed in its lowegposition in positions 1, 2 and 7 of the sequence switch, and its upper position is positions 3, 4 and 8 of the sequence switch. The motor magnet of such switch is The motor magnet 58 which governs the action of the brush selecting spindle 73 is provided with two windings, each of which forms part of a separate exciting circuit. For the sake of convenience, one of these circuits will be termed circuit A, and the other circuit B. Circuit A may be traced as follows: From battery 3, contact 52 of the sequence switch in position 1, line a, back contact of the stop relay 68, armature 82, stepping magnet 67, hook switch 80, line I), left hand winding of the line relay 66, contact spring 53 of the sequence switch in position 1, contact spring 54 of the sequence switch in position 1, upper windin of the motor magnet 58, spring 70, spring 69 to ground. Circuit B may from battery l, right hand winding of the line relay 6e, contact spring 55 of the sequence switch in position 1, lower winding of motor magnet 58, arm 71, spring 69 to ground. It will be observed that circuit B is ClOSud only when the roller carried by the arm 71 is riding on a tooth of the wheel 7 9 for the reason that when the roller rests in a depression between the teeth, the arm 71 does not contact with the spring 69. Also, when the arm 71 is moved outward by a tooth on the wheel 79, the contact between the springs and 69 is broken, thus opening circuit A. The motor magnet 14 of the brush carrving frame is also provided with two windings, each of which is included in a se arate and independent circuit which, for t e sake of convenience, may be termed circuits C and D. Circuit C may be'traced as follows: from battery 3, contact spring 52 of the sequence switch in position 4, line-a, back contact of the stop relay 68, armature 82, stepping magnet 67, book switch 80, line 7), line relay, contact spring 53 of the sequence be traced as follows:

left hand winding 66 of the switch in position 4, contact sprin 54 of I the sequence switch in position 4, rig it hand winding of the motor magnet 1%, spring 77,

sprin 78 to ground. Circuit 1) may be trace as follows: battery 1, right hend winding of relay 66, contact spring 55 of the sequence switch in position 4, left hand winding of the motor magnet 14. arm 76, spring 78 to ground. It will be observed that circuit D is closed only when the roller 83 rests upon the top or crest of one of the teeth on the interrupter segment 12, as when the roller rests in one of the depressions between the teeth, contact between the arm 76 and the spring 78 is broken, also the contact between the spring 78 and spring 77 is made when the roller 83 rests in depression, and is broken when the roller rests on the crest of a tooth.

The operation 0" the system may be stated as follows: The se ector switch will be in normal position and hence the arm 71 will rest in a depression on the tooth wl'ieel '79 and the arm. 83 ill r st in a depression n the spring 0%. lherclore, the springs 70 and 69 will be if: contact and the springs 77 and 78 will be incontact. When the sub scriber removes his receiver from the hook, circuit A as traced above will be closed. This circuit includes the stepping relay, one winding of the line relay 66, one winding of the motor magnet 58 and the springs 70 and 69. Therefore, the line relay and the motor magnet 58 will be energized. The anergizing of the line relay will pull up its armature 15 and wi l close the following circuit for the motor magnet 57 of the sequence switch: battery 4. armature 15, front contact of the line relay, contact spring 56 of the sequence switch in position 1, motor mag;

.briish. The opening of and when this occurs net 57 to ground. Thir will energize the motor magnet 57 and drive the sequence switch into its second position. The spindle 7 3 will also begin to rotate, due to the energization of the motor magnet 58, the upper winding of which will be energized until the arm 71 contacts with the spring 69. As soon, however, as h arm 71 contacts with the spring 69, cir it as above traced is closed. Included in 1 icuit B are the right hand winding of the line relay 66, lower winding of the magnet 58, arm 71 and spring 69 so that while the breaking of a contact between the springs 7 O and 69 opens circuit A, the motor magnet will be energized over the alternative circuit B, and the ins relay will also be energized over this circuit and the armature thereof will not fall back. However, the opening of circuit A at the springs 69 and causes the armature of the stepping magnet 67 to fall back, and causes the sending device to be 'stepped back one step. Inasmuch as circuit B is closed at the arms 71 and 69, re ar'dless of the sending device, whenever t e roller carried by the arm 71 is riding on a tooth of the toothed wheel 79, the rotation of the spindle 7 3 can be stopped only when a roller carried by the arm 71 is located in a depression between the teeth as that is the only position of the lever 71 in which contact is broken between the arms 71 and the spring 69.

The motor magnet 58 will continue to be ener 'zed and the spindle "3 will rotate until asu cient number of imp lses have been sent Pack through the ste ping magnet 67 to step the sendingpdevi'ce back to a .point determined by t e set of brushes ,which it is desired to select, and at such point the stop magnet 68 will operate. The olperation of the stop magnet 68 opens circuit A, Circuit B, however, remains closed until the roller carried by the arm 71 rests in a depression, the motor magnet will be denergized and the spindle will be stopped in a position to select the desired circuit B by the stop magnet 68 also denergizes the line relay 66, which closes at its back contact a circuit for the motor magnet 57 of the se- I which may be traced as follows: battery 4, armature 15, back contact of the line relay 66, contact spring 56 of the sequence switch in position 2, motor magnet 57 to ground. This energizes the motor magnet 57 and drives the sequence switch to position 3. The sending device now begins the second stage of,its movement and the stop magnet 68 is dei nergized, thus closing circuit (3 above traced. This circuit includes the left hand windin of the line relay 6 right hand winding 0 the motor magnet 14, springs 77 and 78. This energizes the line relay 66 and motor magnet 14 so that the brush frame begins to move from its normal quence switch,

position. The energization of the line relay 66 closes the following circuit for the sequence switch: battery 4, armature 15, front contact of the line relay 66, spring 56 of the sequence switch in position 3, motor magnet 57 to ground. This drives the sequence switch to its fourth position. As soon as the brush frame moves from its normal position, roller 83 rides up upon a long tooth, thus closing circuit D and maintaining the motor magnet 14 energized while the brush frame moves from its normal position to the first notch in the interrupter segment 12. It is during this movement that the brush tripping spindle 73 trips the selected set of brushes which are then moved over the stationary contacts 11. As soon as the first depression of the interrupter so out 12 is reached, circuit C will be made y the contact of the springs 77 and 7 8,and thereafter as the roller 83 rides upon the crest of the teeth of the interrupter segment 12, circuit T will be broken and stepping magnet 67 delinergized, and the sender stepped ack-to its normal osition. When the sender reaches the norma position, the stop magnet 68 will be energized, opening circuit C, deiinergizing motor magnet 14 when the roller 83 reacl es the bottom of a notch corresponding to t e terminals that it is desired to select. The brushes will be accurately centered on the desired terminal for the reason tl; Lt circuit D will be maintained until the roller 8 reaches the bottom of the notch in the inter rupter segment 12. I k The operation of the relay 68 also deiinergizes line relay 66 and closes the following circuit for the sequence switch motor imag not 57 battery 4, armature 15. back contact of line relay 66, contact spring 56 of sequence switch in position 4, motor magnet 57'to ground, thus driving sequence switch position 5. After the desired set of terminals has been selected and the rotation of the magnct 68 is defollowing circuit: 52 of sequence contact of relav magnet 67, hool:

brush frame stopped, the energized and c oses the battery 5, contact sprin switch in position 5, bac 68, armature 82, stepping switch 80, line relay 66, contact 53 ot' the sequence switch in osition 6 tothe other side of battery 5. Tlie line relay 66 is ener gized over the circuit just traced and closes at its front contact the following circuit'for the sequence switch motor magnet. battery 4, armature 15, front contact and line rela 66, contact spring 56 of the sequence switc in position 5. motor magnet 57 to mind, moving the sequence switch to ositi six. This is the talking position an the calling subscriber is connected to the called subscriber through the selector.

When the conversation is finished, the talking circuit is opened by hanging up the receivers and the line relay 66 is eenergized and closes through its back contact the following circuit for the motor magnet of the sequence switch: battery 4, armature 15, back contact of the line relay 66, contact spring 56 of the sequence switch in position 6 motor magnet 57, thus driving the sequence switch to position 7. The sequence switch in its seventh position closes the following circuit: battery 2, contact of the sequence switch in position 7, left hand winding 66 of line relay, contact spring 53 of the sequence switch in position 7, contact spring 54 of sequence switch in position 7, upper winding of the motor magnet 58, springs 69 and 70 to ground. The following circuit is also closed by the sequence switch in its seventh position: from battery 4, right hand winding of the line relay 60, contact spring in position 7. lower winding of motor magnet 58, arm 71, spring 69 to ground, this last circuit being closed while the roller carried by the arm 71 is riding upon a tooth of the toothed wheel 71). The spindle 73 will rotate, lasing energized by first one and then the other of these two circuits just traced, 'lepi'aiding upon whether the contact is made by the spring i and arm 71 or springs 69 and 70, until it reaches normal position, when the roller carried y the arm 71 will drop into the deep notch.

When the roller carried by the arm 71 drops into the deep notch as described above, the arm 71 makes contact with the spring 72 and closes a circuit for the motor i'nagnet of the sequence switch. which may be traced as follows: From battery 4, right hand winding of the line relay 66, contact spring 55 of the sequence switch in posi-' tion 7, lower winding of magnet 58, arm 71, spring 72, contact spring 51 of the sequence switch in position 7, motor magnet 57 of the sequence switch to ground. This drives the sequence switch to its eighth position and opens the circuit of the motor magnet 58.

In the eighth position of the sequence switch, the following circuits are closed: from battery 2, contact spring 50 of the sequence switch in position 8, left hand winding of the relay 66, contact spring 53 of the sequence switch in position 8, contact spring 54 of the sequence switch in position 8, right hand winding of the motor magnet 1 1, spring 77, spring 78 to ground; also from battery 4, right hand winding of the relay 66, coi'itact spring 55 of the sequence switch in position 8, left hand winding of the motor magnet 14, arm 76, spring 78 to ground. The motor magnet of the wiper carriage is thus energized from one or the other of these circuits until it is returned to normal position, at which time the roller 83 falls into a depression of the insulated metal segm 65. When, this occurs, the following ffljlbiif dliidI battery t, right haud winding of relay 66, contact spring 55 in position 8 of the sequence switch, left hand winding of the motor magnet 14, arm 76, roller 83, insulated metal segment 64, con tact spring 51 of the sequence switch in position 8, motor magnet 57 of the sequence switch to ground. This drives the sequence switch into normal position and opens the circuit previously established through the motor magnet 14. This leaves all the mechanism in its normal position and ready for the next call.

Although several batteries have been shown as connected to various parts of the circuits, it is understood that these all may be and preferably are art of the central battery at the central 0 cc.

While the system has been described in connection with a selector switch of the type which has been developed by the applicant, obviously the system could be used with any well-known form of selector switch in which motor magnets are used to drive the switch.

Having thus described my invention, what I desire to claim is as follows:

1. In an automatic telephone system, a selector switch comprising stationary contacts and contacts adapted to be moved over said stationary contacts, an electr c-responsive device governing the movement of said movable contacts, and means comprising one of a plurality of independent magnetizing windings for said electroresponsive device adapted to prevent said movable contacts from stopping between two adjacent stationary contacts.

2. In an automatic telephone system, a selector switch comprising stationary contacts and contacts adapted to be moved over said stationary contacts, an electromagnet governing the movement of said movable contacts over said stationary contacts, a pair of independent coils for said electromagnet adapted to control the same, a local circuit for one of said coils ineffective except while the movable contacts of the selector switch are intermediate two adjacent stationary contacts.

3. In an automatic telephone system, a selector switch comprising stationary contacts and contacts adapted to be moved over said stationary contacts, an electromagnet governing the movement of said movable contacts over said stationary contacts, a pair of windings for said electromagnet, a'main and a local controlling circuit for said windings respectively, and a switch actuated in the movement of said selector switch adapted to shift the control of said electromagnet from said main circuit to said local circuit during that portion of the movement of the selector switch in which the movable contacts are intermediate two adjacent stationary contacts.

.rela y controlling 4. In an automatic telephone system, a selector switch comprising stationary contacts and contacts adapted to be moved over said stationary contacts, a magnetic clutch for coupling said movable contacts with a source of power, and a plurality of independent windings for said clutch by which said magnetic clutch may be controlled.

In an automatic telephone system, a selector switch comprising stationary contacts and contacts adapted to be moved over said stationary contacts, a magnetic clutch for connectingsaid movable contacts to a source of power, a plurality of independent magnetizing windings for said magnetic clutch, and a switch actuated by the movement of said selector switch for shifting the control of said clutch from one of said windings to another.

'6. In an automatic telephone system, a selector switch, a line relay and a controlling device, a circuit includingan electro responsive device associated with said controlling device, an clcctroresponsive device as ociated with said selector switch and a. winding of said line relay, said circuit adapted to control the movement of said sclec'tor switch during a part of its movement, and a local circuit including the electro-responsive device associated with said selector switch and a. winding of said line the movement of the selector switch during a part of its movement.

7. In an automatic telephone system, the combination of a selector switch and a send ing device, each adapted to control. and be controlled by the other, a motor magnet having two windings associated with said selector switch, a ste ping magnet associated with said sending evice, a circuit includ ing said stepping, magnet and a winding of said motor magnet, and an additional local circuit including a second winding of said motor magnet...

8. In an automatic telephone systen'i. a sclcctor switch comprising a series of brushes movable over rows of stationary contacts, means movable to select one set of said brushes, an electro-rcs ionsive device for op erating said brush selecting nnan. a inrality of independent circuit over which w ll electro-responsir flital'n is "ldlill'ti to be controlled, wlioiob y t; rie. .il .ior can stop only in one oi' a rcihwrihisw-i number of biush selecting poi-anions,

J. In an autonmtic telnpn u: v;--.tcni, :1 selector switch comprising a series of lunches movable over rows of stationary contacts, a rotatablebrush selecting spiznlie as o iated with said selector switch, a motor magnet for sairi brush selecting spindle, means comprising a plurality of iinh-prinlent cirsuits for said motor ma met to preventthe stopping of said spind e -except when in one of a plurality of brush selecting posi tions.

10. In an automatic telephone s stem, a selector switch comprising a series 0 brushes movable orer ,rows of stationary contacts, a rotatable brush selecting spindle associated with said slm'tol switch, a motor magnet associated with. said brush selecting spindle, a plurality of ndependent con trollizig cirunits for said motor magnet, and a switch actuated. in the movement of the brush selecting spindle for shifting the control of said motor magnet from one of said controlling circuits to another of said controh ling circuits.

ll. In an automatic telephone system the combination ith a sender hating a controling magnet associated therewith; a selector switch having a controlling magnet associatcd thtj-rcwitli. and an interrupter, said magnets and interrupter being cruiueeted in series in fun sans ircuit; of electrical means for prevent maid selector switch from stoppin lic-lnz-i'n two adjacent mint-acts.

ii. In an autonmtic tclcphonc system, a circuit including a controlling magnet of a sender, a mot-or magnet of a selector switch, and an ioterw her in s ries; and means minimis ng an .'-i 'l flfiliul circuit for control" ling said motor magnet while said first named circuit is interrupted. 95

iii. In an automatic lelephoiuem tl'ic combination of selector switch and a sender, each adapted to c mtrol and b con trolled by the other, a. motor magnet and an interrupter associated with said selector switch. and a rontrolling magnet associated with said. sender, said motor magnet, controlling niagnctand iuterru 'iter being con neclcd in :tl'lifi in the same circuit. and electrical m ans for preventing said selector switch iron: .iopping in any exvept one of a plurality i idrlinilistopping pi'isitions.

i rem 

